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<h3><a name="SECTION001614113000000000000000"></a><a name="ctypes-arrays"></a>
<br>
14.14.1.13 Arrays
</h3>

<p>
Arrays are sequences, containing a fixed number of instances of the
same type.

<p>
The recommended way to create array types is by multiplying a data
type with a positive integer:
<div class="verbatim"><pre>
TenPointsArrayType = POINT * 10
</pre></div>

<p>
Here is an example of an somewhat artifical data type, a structure
containing 4 POINTs among other stuff:
<div class="verbatim"><pre>
&gt;&gt;&gt; from ctypes import *
&gt;&gt;&gt; class POINT(Structure):
...    _fields_ = ("x", c_int), ("y", c_int)
...
&gt;&gt;&gt; class MyStruct(Structure):
...    _fields_ = [("a", c_int),
...                ("b", c_float),
...                ("point_array", POINT * 4)]
&gt;&gt;&gt;
&gt;&gt;&gt; print len(MyStruct().point_array)
4
&gt;&gt;&gt;
</pre></div>

<p>
Instances are created in the usual way, by calling the class:
<div class="verbatim"><pre>
arr = TenPointsArrayType()
for pt in arr:
    print pt.x, pt.y
</pre></div>

<p>
The above code print a series of <code>0 0</code> lines, because the array
contents is initialized to zeros.

<p>
Initializers of the correct type can also be specified:
<div class="verbatim"><pre>
&gt;&gt;&gt; from ctypes import *
&gt;&gt;&gt; TenIntegers = c_int * 10
&gt;&gt;&gt; ii = TenIntegers(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
&gt;&gt;&gt; print ii
&lt;c_long_Array_10 object at 0x...&gt;
&gt;&gt;&gt; for i in ii: print i,
...
1 2 3 4 5 6 7 8 9 10
&gt;&gt;&gt;
</pre></div>

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